A man has no reason to be ashamed of having an ape for his grandfather. If there were an ancestor whom I should feel shame in recalling it would rather be a man—a man of restless and versatile intellect—who … plunges into scientific questions with which he has no real acquaintance, only to obscure them by an aimless rhetoric, and distract the attention of his hearers from the real point at issue by eloquent digressions and skilled appeals to religious prejudice.

As recollected in a letter written by an undergraduate, John Richard Green, writing to his friend, afterwards Professor Boyd Dawkins. This was Huxley's rebuttal to Bishop Samuel Wilberforce who ridiculed Darwin's theory of evolution at a meeting of the British Association at Oxford (30 Jun 1860). After hearing Wilberforce's speech, and before rising himself, Huxley is said to have remarked, “The Lord has delivered him into my hands!” (No transcript was taken at the time, so the words are not verbatim. The version above is commonly seen, and was said by Huxley to be fair in substance, if not wholely accurate. The letter excerpt is in Leonard Huxley (ed.), Life and Letters of Thomas Henry Huxley (1916), Vol. 1, 199. Additional accounts of the debate are given in the book.

But for the persistence of a student of this university in urging upon me his desire to study with me the modern algebra I should never have been led into this investigation; and the new facts and principles which I have discovered in regard to it (important facts, I believe), would, so far as I am concerned, have remained still hidden in the womb of time. In vain I represented to this inquisitive student that he would do better to take up some other subject lying less off the beaten track of study, such as the higher parts of the calculus or elliptic functions, or the theory of substitutions, or I wot not what besides. He stuck with perfect respectfulness, but with invincible pertinacity, to his point. He would have the new algebra (Heaven knows where he had heard about it, for it is almost unknown in this continent), that or nothing. I was obliged to yield, and what was the consequence? In trying to throw light upon an obscure explanation in our text-book, my brain took fire, I plunged with re-quickened zeal into a subject which I had for years abandoned, and found food for thoughts which have engaged my attention for a considerable time past, and will probably occupy all my powers of contemplation advantageously for several months to come.

Have you ever plunged into the immensity of space and time by reading the geological treatises of Cuvier? Borne away on the wings of his genius, have you hovered over the illimitable abyss of the past as if a magician’s hand were holding you aloft?

Have you ever plunged into the immensity of time and space by reading the geological tracts of Cuvier? Transported by his genius, have you hovered over the limitless abyss of the past, as if held aloft by a magician’s hand?

If the historical development of science has indeed sometimes pricked our vanity, it has not plunged us into an abyss of immorality ... it has liberated us from misconceptions, and thereby aided us in our moral progress.

If you take a plunge into the sea, you unconsciously close your pores against the cold. If you go out on a cold day, you consciously put on an overcoat. Science can give you reason why you should not make & put on an overcoat without knowing it just as you shut your pores.

In fact, the thickness of the Earth's atmosphere, compared with the size of the Earth, is in about the same ratio as the thickness of a coat of shellac on a schoolroom globe is to the diameter of the globe. That's the air that nurtures us and almost all other life on Earth, that protects us from deadly ultraviolet light from the sun, that through the greenhouse effect brings the surface temperature above the freezing point. (Without the greenhouse effect, the entire Earth would plunge below the freezing point of water and we'd all be dead.) Now that atmosphere, so thin and fragile, is under assault by our technology. We are pumping all kinds of stuff into it. You know about the concern that chlorofluorocarbons are depleting the ozone layer; and that carbon dioxide and methane and other greenhouse gases are producing global warming, a steady trend amidst fluctuations produced by volcanic eruptions and other sources. Who knows what other challenges we are posing to this vulnerable layer of air that we haven't been wise enough to foresee?

Samuel Pierpoint Langley, at that time regarded as one of the most distinguished scientists in the United States … evidently believed that a full sized airplane could be built and flown largely from theory alone. This resulted in two successive disastrous plunges into the Potomac River, the second of which almost drowned his pilot. This experience contrasts with that of two bicycle mechanics Orville and Wilbur Wright who designed, built and flew the first successful airplane. But they did this after hundreds of experiments extending over a number of years.

The individual on his own is stable only so long as he is possessed of self-esteem. The maintenance of self-esteem is a continuous task which taxes all of the individual’s powers and inner resources. We have to prove our worth and justify our existence anew each day. When, for whatever reason, self-esteem is unattainable, the autonomous individual becomes a highly explosive entity. He turns away from an unpromising self and plunges into the pursuit of pride—the explosive substitute for self-esteem. All social disturbances and upheavals have their roots in crises of individual self-esteem, and the great endeavor in which the masses most readily unite is basically a search for pride.

In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion.
(1987) -- Carl Sagan